Ya don't make it easy do ya man there's a BUNCH of planes that would be nice but they all have the engine inverted... you could probably mount any of them sidewinder but you'll have to move the motor mount... not sure you want to do that. Your FL-70 should run fine inverted... you just have to get the tank height and needles right if you reconsider the inverted mounting you have many option's... either that or plan on giving up the cowl... there is this plane http://www.horizonhobby.com/Products...ProdID=HAN4100 not sure it's aerobatic enough for ya though.

John